Discusión. Buenos Aires: Emecé, 1957. 180 pp. [Revised and expanded second edition, as part of the series of single volumes of the Obras completas. Essays starting with "Nota sobre Walt Whitman" were added to this edition.]

Ana María Barrenecha. La expresión de la irrealidad en la obra de Jorge Luis Borges. Mexico City: El Colegio de México, 1957. [Second edition published by Paidós in Buenos Aires in 1967. English version from New York University Press in 1965.]